.
America had a tax rate of 91% on the obscenely wealthy for decades and around 70% until the 80s. Reducing this to historical lows has universally, by both bipartisan and nonpartisan[2] parties, been found to have been the primary driver of inequality[1].
At even an absurd 99% tax rate, applied equally instead of tiered, Michael Dell would have $1.5 billion dollars.
[1]: https://publicintegrity.org/inequality-poverty-opportunity/t... [2]: https://sgp.fas.org/crs/misc/R42729.pdf